Earlier this year a deep sea photographer, Yoji Ookata, was diving off the southern coast of Japan. Ookata has been documenting his explorations of the deep seas for more than 50 years, but during this dive he saw something he had never witnessed before. A circular pattern of rippling sand about 80 feet below sea level and what he estimated to be about 6 feet in diameter was on the ocean floor.

The find stunned him so much that he went off and returned to the same location with a full TV camera crew accompanying him. He hoped to find a reason for the mysterious pattern on the sea bed he had found.

He described to people that he had found a "mystery circle" and they became known as the Japan Crop Circles, referring to the unusual mysterious circles found in crop fields in various locations across the globe.

With more than 70 percent of the Earth being covered in water, scientists admit there are still millions of mysteries and discoveries to be uncovered in the deep seas. According to the National Oceanic and Atmospheric Administration, 95 percent of what exists underwater still has not been seen by human eyes.

It has also been highlighted that NASA has openly admitted that currently mankind has a better map of the surface of Mars than that of the bottom of the oceans.

The mysteries of the deep made Ookata's find that much more interesting. However, after further investigation Ookata has seemingly found the cause of the Japan Crop Circles.

He finally came to discover that the mystery circle was in fact created by a single puffer fish, which was just a few inches long.

Ookata has witnessed the fish working tirelessly to create the circle, which appears to have a number of purposes; firstly, female fish seem to be attracted to the ridges and valleys created in the sand by the circles. The female fish tour the circle and then deposit their eggs into the center. The ridges also protect the eggs from the strong ocean currents.